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An offshore trust does not get its legal standing from being hidden. It gets its legal standing from being reported correctly, every year, on time. US law does not prohibit a US person from establishing a trust in the Cook Islands or Nevis, transferring assets to a foreign trustee, or opening an account at an offshore bank. What US law requires is disclosure. Four IRS forms carry that disclosure burden, and missing any one of them turns a fully legal structure into a compliance problem that can cost far more than the trust itself.
Offshore Broker is a Cook Islands-based offshore structuring firm. Our team includes Connor Steens, who brings experience from the Cook Islands’ oldest licensed trustee company, and John Evans, who brings private banking sector experience from the Cook Islands. We build every Cook Islands Trust to be documentation-ready for these filings from the day it is registered.
This guide covers the four forms a US settlor of an offshore trust needs to know, what each one reports, when it is due, and what happens when a deadline slips.
The Four Forms That Matter
A US person who establishes or funds a foreign trust, or who holds a foreign bank account, has reporting obligations that sit entirely apart from the trust deed itself. The trustee in Rarotonga or Charlestown has no US filing duty. The obligation belongs to the settlor, and in some cases to the beneficiaries. Four forms cover almost every scenario:
Form 3520 reports transactions between a US person and a foreign trust. Form 3520-A is the foreign trust’s own annual information return. FBAR (FinCEN Form 114) reports foreign financial accounts. Form 8938 reports specified foreign financial assets under FATCA. A properly structured offshore asset protection plan accounts for all four from the outset, not as an afterthought once the structure is already funded.
Form 3520: Reporting Transactions With the Trust
Form 3520 is filed by the settlor in any year assets move into the trust, and by beneficiaries in any year they receive a distribution. The form reports the amount transferred, the identity of the trust, and the nature of the transaction. It is due on the same date as the settlor’s individual tax return, including extensions, and it is filed separately from Form 1040, not attached to it.
The threshold for triggering a filing is low. A single wire transfer funding the trust, even a modest one, requires the form for that tax year. Distributions from the trust back to a US beneficiary also trigger the requirement, regardless of size. Settlors who fund a structure gradually, moving assets over several years rather than all at once, need a Form 3520 for every year a transfer occurs.
Form 3520-A: The Trust’s Own Annual Return
Form 3520-A is technically the trustee’s obligation, but in practice a US settlor’s advisor prepares it, since most foreign trustees do not file US tax forms as a matter of course. The form reports the trust’s income, its balance sheet, and distributions made during the year. It is due March 15, two months earlier than the settlor’s own return, though a six-month extension is available on Form 7004.
Because a Cook Islands Trust funded by a US settlor is treated as a grantor trust, this form does the work of confirming that every dollar of trust income flows through to the settlor’s personal return. The IRS looks through the structure entirely. Nothing about the trust reduces, defers, or shelters US tax liability. See our guide on how a Cook Islands Trust is taxed for the mechanics of that pass-through treatment.
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FBAR and Form 8938: Reporting the Accounts Underneath
The trust deed is one layer of reporting. The accounts inside the structure are another. Any US person with signature authority or a financial interest in a foreign bank account, brokerage account, or similar asset must file FBAR if the aggregate value of all foreign accounts exceeds $10,000 at any point during the year. This includes accounts held by an offshore LLC that the settlor manages day to day, even before a trustee formally takes control.
Form 8938 covers a broader category of specified foreign financial assets under FATCA and applies at higher thresholds that vary by filing status and residency. Unlike FBAR, which is filed with FinCEN separately from the tax return, Form 8938 attaches directly to Form 1040. A settlor holding an offshore bank account through the offshore banking arrangement inside a trust structure typically needs both filings, not one or the other.
What Happens When a Filing Is Missed
The penalties scale with the size of what was not reported, and they escalate quickly. A missed Form 3520 or 3520-A starts at $10,000 per form per year, or a percentage of the transaction value if that figure is higher, and can climb toward 35% of the amount involved. FBAR penalties for non-willful violations can reach $10,000 per account per year; willful violations can reach the greater of $100,000 or 50% of the account balance, for each year the account went unreported.
These figures explain why the IRS treats reporting as the actual legal boundary around offshore structures, not a secondary detail. A settlor who transfers $2,000,000 into a properly drafted, fully reported Cook Islands Trust has done something entirely lawful. A settlor who does the same transfer and skips the paperwork has created a liability that can exceed the value of the trust itself within a few missed years.
Fixing a Missed Filing Before the IRS Finds It
A missed year is not automatically a lost cause. The IRS maintains procedures specifically for taxpayers who discover a gap in their own reporting before the IRS discovers it independently. The Delinquent FBAR Submission Procedures let a taxpayer file missed FBARs directly, with a statement explaining the reason for the delay, and the IRS generally does not impose a penalty when the underlying income was properly reported and taxed. The Streamlined Filing Compliance Procedures go further, covering missed Form 3520, 3520-A, and 8938 filings alongside FBAR for taxpayers whose failure was non-willful, in exchange for amended returns covering the relevant years and a reduced miscellaneous offshore penalty rather than the full statutory penalty.
The distinction that matters most is timing relative to IRS contact. Both programs are available only before the IRS has opened an examination or otherwise identified the taxpayer’s noncompliance. A settlor who realizes a Form 3520 was missed two years ago and files under these procedures voluntarily is in a materially different position than one who receives an IRS notice first and tries to explain the gap afterward. This is also why a CPA experienced with foreign trust reporting matters as much as the trust structure itself: catching a gap early, and knowing which cure procedure applies, generally changes the outcome from a five- or six-figure penalty to a manageable filing correction.
Who Actually Prepares These Filings
A trustee in the Cook Islands or Nevis administers the trust under local law. A US-licensed CPA prepares the US filings. These are separate functions handled by separate professionals, and a structure that conflates the two, or leaves the filings to chance, is the structure most likely to run into trouble. Offshore Broker does not prepare tax filings directly, but every trust we register is built with the documentation a CPA needs already in place: clear transfer records, a properly drafted trust deed, and account statements formatted for US reporting purposes.
For settlors evaluating whether an offshore structure fits their situation, the compliance workload is a real part of that decision, alongside cost and litigation exposure. See our overview of Cook Islands Trust compliance for the full annual calendar, and our guide on whether a Cook Islands Trust is legal for the broader legal framework these filings sit inside.
